Integrated circuit having multiple modes of operation

ABSTRACT

A method according to one embodiment may include operating an integrated circuit in a selected mode of operation. The integrated circuit may include processor circuitry and interface circuitry. The processor circuitry may include a plurality of processor cores. The interface circuitry may be capable of communicating in accordance a plurality of different protocols. At least one of the processor cores may be capable of issuing a command to the interface circuitry to communicate in accordance with at least one of the plurality of different protocols that corresponds to the selected mode of operation of the integrated circuit.

CROSS-REFERENCE TO RELATED APPLICATION

The subject application is related to co-pending U.S. patent applicationSer. No. Yet To Be Assigned (Attorney Docket No. 42390.P14962), entitled“Integrated Circuit Having Multiple Modes Of Operation,” which is beingfiled concurrently with the subject application.

FIELD

This disclosure relates to an integrated circuit having multiple modesof operation.

BACKGROUND

In one conventional data storage arrangement, a computer node includes ahost bus adapter (HBA). The HBA communicates with host devices via thehost bus using a host bus protocol associated with the host bus. The HBAalso communicates with a data storage system via one or morecommunication links using a communication protocol associated with theone or more links. If the data storage system includes a redundant arrayof independent disks (RAID), the HBA typically also carries outRAID-related operations (e.g., operations involved in implementing theRAID).

The HBA includes a plurality of integrated circuit chips that the HBAuses to carry out communications between the HBA and the host processor,communications between the HBA and the data storage system, and theoperations involved in implementing the RAID. Typically, theseintegrated circuit chips limit the communication capabilities of the HBAsuch the HBA is capable of using only a single predetermined host busprotocol and only a single predetermined communication protocol.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of embodiments of the claimed subject matterwill become apparent as the following Detailed Description proceeds, andupon reference to the Drawings, wherein like numerals depict like parts,and in which:

FIG. 1 is a diagram illustrating a system embodiment.

FIG. 2 is a diagram illustrating in greater detail an integrated circuitin the system embodiment of FIG. 1.

FIG. 3 is a diagram illustrating in greater detail interface circuitryin the integrated circuit of FIG. 2.

FIG. 4 is a diagram illustrating another system embodiment.

FIG. 5 is a flowchart illustrating operations that may be performedaccording to an embodiment.

Although the following Detailed Description will proceed with referencebeing made to illustrative embodiments, many alternatives,modifications, and variations thereof will be apparent to those skilledin the art. Accordingly, it is intended that the claimed subject matterbe viewed broadly, and be defined only as set forth in the accompanyingclaims.

DETAILED DESCRIPTION

FIG. 1 illustrates a system embodiment 100 of the claimed subjectmatter. System 100 may include a host processor 12 coupled to a chipset14. Host processor 12 may comprise, for example, an Intel® Pentium® IVmicroprocessor that is commercially available from the Assignee of thesubject application. Of course, alternatively, host processor 12 maycomprise another type of microprocessor, such as, for example, amicroprocessor that is manufactured and/or commercially available from asource other than the Assignee of the subject application, withoutdeparting from this embodiment.

Chipset 14 may comprise a host bridge/hub system that may couple hostprocessor 12, a system memory 21 and a user interface system 16 to eachother and to a bus system 22. Chipset 14 may also include an I/Obridge/hub system (not shown) that may couple the host bridge/bus systemto bus 22. Chipset 14 may comprise integrated circuit chips, such asthose selected from integrated circuit chipsets commercially availablefrom the assignee of the subject application (e.g., graphics memory andI/O controller hub chipsets), although other integrated circuit chipsmay also, or alternatively be used, without departing from thisembodiment. User interface system 16 may comprise, e.g., a keyboard,pointing device, and display system that may permit a human user toinput commands to, and monitor the operation of, system 100.

Bus 22 may comprise a bus that complies with the Peripheral ComponentInterconnect (PCI) Express™ Base Specification Revision 1.0, publishedJul. 22, 2002, available from the PCI Special Interest Group, Portland,Oreg., U.S.A. (hereinafter referred to as a “PCI Express™ bus”).Alternatively, bus 22 instead may comprise a bus that complies with thePCI-X Specification Rev. 1.0a, Jul. 24, 2000, available from theaforesaid PCI Special Interest Group, Portland, Oreg., U.S.A.(hereinafter referred to as a “PCI-X bus”). Also alternatively, bus 22may comprise other types and configurations of bus systems, withoutdeparting from this embodiment.

Controller card 20 may be coupled to and control the operation of massstorage 28. In this embodiment, mass storage 28 may comprise, e.g., oneor more redundant arrays of inexpensive disks (RAID) 29. The RAID levelthat may be implemented by RAID 29 may be 0, 1, or greater than 1.

Processor 12, system memory 21, chipset 14, bus 22, and circuit cardslot 30 may be comprised in a single circuit board, such as, forexample, a system motherboard 32. Mass storage 28 may be comprised inone or more respective enclosures that may be separate from theenclosure in which the motherboard 32 and the components comprised inthe motherboard 32 are enclosed.

Card 20 may be coupled to mass storage 28 via one or more networkcommunication links 44. As is discussed in below, depending at least inpart upon the operating mode of an integrated circuit 40 that may becomprised in card 20, card 20 may exchange data and/or commands withmass storage 28, via links 44, using one or more of a variety ofdifferent communication protocols, e.g., Fibre Channel (FC), SerialAdvanced Technology Attachment (S-ATA), and/or Serial Attached SmallComputer Systems Interface (SAS) protocol. Of course, alternatively, I/Ocontroller card 20 may exchange data and/or commands with mass storage28 using other and/or additional communication protocols, withoutdeparting from this embodiment.

In accordance with this embodiment, if a FC protocol is used bycontroller card 20 to exchange data and/or commands with mass storage28, it may comply or be compatible with the interface/protocol describedin ANSI Standard Fibre Channel (FC) Physical and Signaling Interface-3X3.303:1998 Specification. Alternatively, if a S-ATA protocol is used bycontroller card 20 to exchange data and/or commands with mass storage28, it may comply or be compatible with the protocol described in“Serial ATA: High Speed Serialized AT Attachment,” Revision 1.0,published on Aug. 29, 2001 by the Serial ATA Working Group. Furtheralternatively, if a SAS protocol is used by controller card 20 toexchange data and/or commands with mass storage 28, it may comply or becompatible with the protocol described in “Information Technology—SerialAttached SCSI (SAS),” Working Draft American National Standard ofInternational Committee For Information Technology Standards (INCITS)T10 Technical Committee, Project T10/1562-D, Revision 2b, published 19Oct. 2002, by American National Standards Institute (hereinafter termedthe “SAS Standard”) and/or later-published versions of the SAS Standard.

Depending upon, for example, whether bus 22 comprises a PCI Express™ busor a PCI-X bus, circuit card slot 30 may comprise, for example, a PCIExpress™ or PCI-X bus compatible or compliant expansion slot orinterface 36. Interface 36 may comprise a bus connector 37 may beelectrically and mechanically mated with a mating bus connector 34 thatmay be comprised in a bus expansion slot or interface 35 in circuit card20.

Circuit card 20 may comprise an integrated circuit 40, operating modeselector circuitry 42, computer-readable boot code memory 39, andcomputer-readable memory 38. Alternatively, although not shown in theFigures, integrated circuit 40 may comprise memory 38 and/or memory 39.As used herein, an “integrated circuit” means a semiconductor deviceand/or microelectronic device, such as, for example, a semiconductorintegrated circuit chip. Memories 38 and/or 39 each may comprise one ormore of the following types of memories: semiconductor firmware memory,programmable memory, non-volatile memory, read only memory, electricallyprogrammable memory, random access memory, flash memory, magnetic diskmemory, and/or optical disk memory. Either additionally oralternatively, memories 38 and/or 39 each may comprise other and/orlater-developed types of computer-readable memory.

Machine-readable firmware program instructions may be stored in memory38. As described below, these instructions may be accessed and executedby integrated circuit 40. When executed by integrated circuit 40, theseinstructions may result in integrated circuit 40 performing theoperations described herein as being performed by integrated circuit 40.

Slot 30 and card 20 are constructed to permit card 20 to be insertedinto slot 30. When card 20 is properly inserted into slot 30, connectors34 and 36 become electrically and mechanically coupled to each other.When connectors 34 and 36 are so coupled to each other, card 20 becomeselectrically coupled to bus 22 and may exchange data and/or commandswith system memory 21, host processor 12, and/or user interface system16 via bus 22 and chipset 14.

Alternatively, without departing from this embodiment, the operativecircuitry of card 20 may not be comprised in card 20, but instead, maybe comprised in other structures, systems, and/or devices. These otherstructures, systems, and/or devices may be, for example, comprised inmotherboard 32, coupled to bus 22, and exchange data and/or commandswith other components (such as, for example, system memory 21, hostprocessor 12, and/or user interface system 16) in system 100.

FIG. 2 is a diagram of integrated circuit 40. Integrated circuit 40comprises processor circuitry 202, I/O interface circuitry 204, memorycontrol circuitry 232, memory control circuitry 230, processor bus 206,and bus bridge circuitry 208. Processor circuitry 202, I/O interfacecircuitry 204, memory control circuitry 232, memory control circuitry230, and bus bridge circuitry 208 may be electrically coupled to, andexchange data and/or commands via, bus 206. Bus bridge circuitry 208 mayelectrically couple processor bus 206 to input/output (I/O) bus 254, andmay permit devices that may be coupled to bus 206 to exchange dataand/or commands with devices that may be coupled to bus 254, whilepermitting the respective address spaces of buses 206 and 254 to beisolated from each other. Memory control circuitry 230, host businterface circuitry 210, boot code memory interface 242, and peripheralinterface circuitry 244 also may be electrically coupled to bus 254, andmay exchange data and/or commands among each other via bus 254. Memorycontrol circuitry 230 may be electrically coupled to memory 38. Bootcode memory interface 242 may be coupled to memory 39. Memory controlcircuitry 232 may be electrically coupled to computer-readable memory228. Memory 228 may comprise, for example, multi-port static randomaccess memory (SRAM), although memory 228 may comprise other types ofcomputer-readable memory without departing from this embodiment. Hostbus interface circuitry 210 may be electrically coupled host businterface 35.

Mode selector circuitry 42 may be electrically coupled to generalpurpose I/O interface circuitry 248 that may be comprised in interfacecircuitry 246. Interface circuitry 246 may comprise other and/oradditional types of interface circuitry (not shown) without departingfrom this embodiment. The interface circuitry comprised in interface 246may be coupled together via, for example, a peripheral bus (not shown)Interface 246 may be coupled to bus 254 via peripheral interfacecircuitry 244 that may permit the interface circuitry in circuitry 246that may be coupled to the peripheral bus in circuitry 246 to exchangedata and/or commands with devices that may be coupled to bus 254.

Boot code memory interface circuitry 242 may permit program instructionsstored in memory 39 to be retrieved therefrom and executed by processorcircuitry 202, after, for example, a reset of integrated circuit 40.More specifically, processor circuitry 202 may provide one or morecommands to memory 39 and/or interface circuitry 242, via bus 206,bridge circuitry 208, bus 254, and interface circuitry 242, that mayresult such program instructions being retrieved from memory 39 andprovided to circuitry 202, via interface 242, bus 254, bridge circuitry208, and bus 206.

Integrated circuit 40 also may comprise performance monitoring (PMON)circuitry 226. PMON circuitry 226 may monitor, e.g., exchange of dataand/or commands carried out via bus 206 and/or bus 254, and/or otherand/or additional operations carried out by other circuitry inintegrated circuit 40, and may determine, based at least in part uponsuch monitoring, whether integrated circuit 40 is operating properly.PMON circuitry 226 may indicate the results of its monitor activitiesto, e.g., processor circuitry 202 and/or external devices, such as, forexample, host processor 12 via circuitry 210.

Processor circuitry 202 may include a plurality of processor cores 216and 218. As used herein, a “processor core” may comprise hardwiredcircuitry, programmable circuitry, and/or state machine circuitry. Also,as used herein, “processor circuitry” may comprise hardwired circuitry,programmable circuitry, and/or state machine circuitry. In thisembodiment, each processor core 216 and 218 may comprise respectivecircuitry that may be compatible and/or in compliance with the Intel®XScale™ Core micro-architecture described in Intel® XScale™ CoreDevelopers Manual, published December 2000 by the Assignee of thesubject application. Of course, as stated above, circuitry 202 maycomprise other types of processor core circuitry without departing fromthis embodiment. In this embodiment, processor cores 216 and 218 maycomprise, for example, computer-readable program instruction memory 220and 224, respectively, that may contain respective sets of micro-codeprogram instructions that processor cores 216 and 218, respectively, mayexecute. The execution of these respective sets of program instructionsby processor cores 216 and 218, respectively, may result in, forexample, the carrying out by circuitry 202, core 216, and/or core 218 ofoperations described herein as being carried out by circuitry 202, core216, and/or core 218, respectively. At least a portion of theserespective sets of program instructions may be retrieved from, e.g.,boot code memory 39 after, for example, a reset of integrated circuit40. Processor core 216 also may comprise a level-2 cache memory 222 thatmay be used by processor core 216 in carrying out the operationsdescribed herein as being carried out by processor core 216.

Interface circuitry 204 may comprise protocol engines 250A, 250B, . . .250N and physical layer interface circuitry 252A, 252B, . . . 252N. Asdescribed below, each respective protocol engine 250A,. 250B, . . . 250Nmay be associated with, and exchange data and/or commands withrespective physical layer interface circuitry 252A, 252B, . . . 252N.Thus, for example, protocol engine 250A may be associated with, andexchange data and/or commands with physical layer interface circuitry252A, protocol engine 250B may be associated with, and exchange dataand/or commands with physical layer interface circuitry 252B, andprotocol engine 250A may be associated with, and exchange data and/orcommands with physical layer interface circuitry 252N, respectively. Inthis embodiment, the respective construction and operation of each ofthe protocol engines 250A, 250B, . . . 250N may be respectivelyidentical. Additionally, in this embodiment the respective constructionand operation of each of the interfaces 252A, 252B, . . . 252N may berespectively identical. Without departing from this embodiment, therespective numbers of protocol engines 252A, 252B, . . . 252N, physicallayer interfaces 252A, 252B, . . . 252N, and links 44 may vary. However,in this embodiment, the number of protocol engines 250A, 250B, . . .250N may be equal to the number of physical layer interfaces 252A, 252B,. . . 252N. In this embodiment, each of the physical layer interfaces252A, 252B, . . . 252N may be coupled to a respective one of the links44; therefore, in this embodiment, the number of physical layersinterfaces 252A, 252B, . . . 252N may be equal to the number of links44.

Host bus interface circuitry 210 may comprise respective interfacecircuitry that may be used to permit integrated circuit 40 to be able toexchange, in accordance with one of a plurality of different host busprotocols with which bus 22 may comply or be compatible, data and/orcommands with other devices that may be coupled to bus 22. For example,in this embodiment, circuitry 210 may comprise PCI-X bus interfacecircuitry 212 and PCI Express™ bus interface circuitry 214. That is, asdiscussed below, depending, at least in part, upon the bus protocol withwhich bus 22 may comply or be compatible, a particular operating mode ofintegrated circuit 40 may be selected in which only a single appropriateone of the respective interface circuitry in circuitry 210 may beenabled to exchange data and/or commands with devices that may becoupled to bus 22, other respective interface circuitry in circuitry 210may be disabled. For example, in this embodiment, if bus 22 is a PCI-Xbus, then, in the selected operating mode, PCI-X interface circuitry 212may be enabled and PCI Express™ bus interface circuitry 214 may bedisabled. Conversely, in this embodiment, if bus 22 is a PCI-X bus,then, in the selected operating mode, PCI-X interface circuitry 212 maybe disabled and PCI Express™ bus interface circuitry 214 may be enabled.

Although not shown in the Figures, in this embodiment, memory controlcircuitry 232 and/or DMA circuitry 234 may be electrically coupled tobus 254. In this embodiment, memory control circuitry 232 may comprisedirect memory access (DMA) circuitry 234. Memory control circuitry 232may control storage of data in, and retrieval of data from memory 228.For example, in this embodiment, memory control circuitry 232 mayexchange commands and/or data with, for example, processor circuitry202, interface circuitry 204, interface circuitry 210 and/or memorycontrol circuitry 230. Based, at least in part, upon these commands,memory control circuitry 232 may exchange data and/or commands withmemory 228. This may result in memory 228 storing and/or retrieving datain accordance with the commands and/or data supplied to memorycontroller circuitry 232. Additionally, depending upon the selected modeof operation of integrated circuit 40, DMA circuitry 234 may control,based upon commands and/or data received by circuitry 234 from othercircuitry in integrated circuit 40, the exchange among I/O interface 204and the other circuitry in integrated circuit 40 of data and/or commandsreceived or intended to be transmitted by I/O interface circuitry 204via one or more links 44. Without departing from this embodiment, DMAcircuitry 234 may not be comprised in circuitry 232, but instead, maycomprise circuitry that is distinct from circuitry 232, and is coupledto circuitry 232 and bus 254.

In this embodiment, memory control circuitry 230 may comprise RAIDoperation-related circuitry 240. Circuitry 240 may comprise, forexample, DMA circuitry 238 and RAID calculation circuitry 236. Memorycontrol circuitry 230 may control storage of data in, and retrieval ofdata from external memory 38. For example, in this embodiment, memorycontrol circuitry 230 may exchange commands and/or data with, forexample, processor circuitry 202, interface circuitry 210 and/or memorycontrol circuitry 232. Based, at least in part, upon these commands,memory control circuitry 230 may exchange data and/or commands withmemory 38. This may result in memory 38 storing and/or retrieving datain accordance with the commands and/or data supplied to memorycontroller circuitry 232. Additionally, depending upon the selected modeof operation of integrated circuit 40, DMA circuitry 238 may control,based upon commands and/or data received by circuitry 238 from othercircuitry in integrated circuit 40, the exchange of RAID-related dataamong such other circuitry in integrated circuit 40. As used herein,“RAID-related data” means data involved in, generated as a result of,used as input or operands in, and/or used in carrying out and/or tofacilitate operations involved in implementing and/or maintaining aRAID, such as, for example, RAID 29. RAID calculation circuitry 236 maycomprise arithmetic accelerator circuitry (not shown) that may becapable of performing one or more arithmetic and/or logical operationsusing and/or involving RAID-related data, such as, for example, logicalexclusive or operations that may generate RAID parity data from initialuser data and/or regenerate the initial user data from such RAID paritydata. Without departing from this embodiment, DMA circuitry 238 and/orRAID calculation circuitry 236 may not be comprised in circuitry 230,but instead, may comprise circuitry that is distinct from circuitry 230,and is coupled to circuitry 230 and bus 254. Also without departing fromthis embodiment, integrated circuit 40 may not comprise RAID calculationcircuitry 236, but alternatively, depending, at least in part, upon theselected operating mode of integrated circuit 40, the arithmetic and/orlogical operations performed by circuitry 236 instead may be performedby processor core 216.

As stated previously, the respective construction of each of theprotocol engines 250A, 250B, . . . 250N may be identical. FIG. 3 is adiagram that illustrates protocol engine 250A. Protocol engine 250A maycomprise data transport layer protocol and data link layer protocolcircuitry 304 and control circuitry 302. Data transport layer protocoland data link layer protocol circuitry 304 may be electrically coupledto control circuitry 302, bus 206, and physical layer interfacecircuitry 252A associated with protocol engine 250A. In this embodiment,circuitry 304 may include a plurality of different respective datatransport layer protocol circuitry 306A, 306B, . . . 306M and aplurality of different respective data link layer protocol circuitry308A, 308B, . . . 308M that may be respectively associated with thedifferent respective data transport layer protocol circuitry 306A, 306B,. . . 306M. For example, in this embodiment, data transport layerprotocol circuitry 306A may be associated with and electrically coupledto data link layer protocol circuitry 308A, data transport layerprotocol circuitry 306B may be associated with and electrically coupledto data link layer protocol circuitry 308B, and data transport layerprotocol circuitry 306M may be associated with and electrically coupledto data link layer protocol circuitry 308M, respectively.

In this embodiment, data transport layer protocol circuitry 306A, 306B,. . . 306M may be capable of carrying out different respective datatransport layer communication protocols that may be associated withand/or comprised in the different respective communication protocolsaccording to which card 20 may communicate with mass storage 28 via oneor more links 44. Similarly, data link layer protocol circuitry 308A,308B, . . . 308M may be capable of carrying out different respectivelink layer communication protocols that may be associated with and/orcomprised in the different respective communication protocols accordingto which card 20 may communicate with mass storage 28 via one or morelinks 44. Each respective data transport layer protocol circuitry 306A,306B, . . . 306M may be associated with and coupled to the respectivelink layer protocol circuitry 308A, 308B, . . . 308M that may be capableof carrying out the respective data link layer protocol that may beassociated with and/or comprised in the same respective communicationprotocol as the respective data transport layer protocol that may becarried out that respective data transport layer protocol circuitry306A, 306B, . . . 306M, respectively. For example, in this embodiment,circuitry 306A and circuitry 308A may be capable of carrying out a datatransport layer protocol and a data link layer protocol, respectively,that may be associated with and/or comprised in the data transport layerprotocol and data link layer protocol, respectively, used in an SASprotocol. Also for example, in this embodiment, circuitry 306B andcircuitry 308B may be capable of carrying out a data transport layerprotocol and a data link layer protocol, respectively, that may beassociated with and/or comprised in the data transport layer protocoland data link layer protocol, respectively, used in an FC protocol.Additionally, for example, in this embodiment, circuitry 306M andcircuitry 308M may be capable of carrying out a data transport layerprotocol and a data link layer protocol, respectively, that may beassociated with and/or comprised in the data transport layer protocoland data link layer protocol, respectively, used in an S-ATA protocol.The number and types of different data transport layer and data linklayer communication protocols that may be implemented by circuitry 304.

When active, each respective data transport layer protocol circuitry306A, 306B, . . . 306M may be capable of providing control and/or datasignals, in response, at least in part, to commands and/or data receivedfrom processor core 218 and in accordance with the respective datatransport layer protocol carried out by the respective circuitry 306A,306B, . . . 306M, to the respective data link layer circuitry 308A,308B, . . . 308M with which the respective circuitry 306A, 306B, . . .306M is associated. This may result in respective data link layerprotocol circuitry 308A, 308B, . . . 308M that receives such controland/or data signals, providing corresponding control and/or datasignals, in accordance with the respective data link layer protocolcarried out by that respective data link layer circuitry, to physicallayer interface circuitry 252A. This may result in physical layerinterface circuitry 252A transmitting to mass storage 28, via one of thelinks 44, corresponding data and/or control signals, in accordance withthe respective communication protocol (e.g., SAS, FC, or S-ATA) thatcomprises the respective data link layer protocol carried out by thatrespective data link layer circuitry.

Likewise, in this embodiment, physical layer interface circuitry 252Amay receive data and/or control signals, in accordance with therespective communication protocol (e.g., SAS, FC, or S-ATA) utilized bythe link in links 44 to which it is coupled, from mass storage 28.Depending at least in part upon the selected mode of operation ofintegrated circuit 40, physical layer interface circuitry 252A mayprovide the received data and/or control signals to data link layerprotocol circuitry 308A, 308B, . . . 308M may be active in the selectedmode of operation. This may result in the active data link layerprotocol circuitry generating and supplying to the data transport layerprotocol circuitry with which it is associated, in accordance with therespective data link layer protocol carried out by the active data linklayer protocol circuitry, corresponding control and/or data signals foruse by this data transport layer protocol circuitry. This may result inthis transport layer protocol circuitry generating, in accordance withthe data transport layer protocol carried out by this transport layerprotocol circuitry, corresponding data and/or commands that may beintended for use, e.g., by an application program executed by processorcircuitry 202 and/or host processor 12. Processor core 218 may signalmemory control circuitry 232, interface circuitry 210, interfacecircuitry 204, and/or DMA circuitry 234. This may result in, forexample, the data and/or commands generated by this transport layerprotocol circuitry being stored in memory 228, provided to processorcore 218, and/or provided to host processor 12 for use by, e.g., thisapplication program.

In this embodiment, in response, at least in part to one or morecommands received by interface circuitry 204 from, for example,processor core 218, control circuitry 302 in protocol engine 250A mayselect which of data transport layer protocol circuitry 306A, 306B, . .. 306M and which of data link layer protocol circuitry 308A, 308B, . . .308M may be active and/or operational. That is, as discussed below,depending upon the selected mode of operation of integrated circuit 40,processor core 218 may provide to interface circuitry 204 one or morecommands associated with this selected operating mode. This may resultin control circuitry 302 signaling circuitry 304. This may result inonly one of the transport layer protocol circuitry 306A, 306B, . . .306M (e.g., circuitry 306A) and only one of the data link layer protocolcircuitry 308A, 308B, . . . 308M (e.g., circuitry 308A associated withcircuitry 306A) associated with the selected operating mode ofintegrated circuit 40 being active and/or operational in protocol engine250A. As a result, protocol engine 250A may only communicate with massstorage 28 in accordance with the communication protocol (e.g., SASprotocol) that comprises and/or is associated with the transport anddata link layer protocols carried out by the active transport and datalink layer circuitry 306A and 308A, respectively, in protocol engine250A. Thus, the selection of the mode of operation of integrated circuit40 may correspond to and result in generation of one or more commands byprocessor core 218 that may result in the selection of which of thetransport and data link layer protocol circuitry may be active and/oroperational in protocol engine 250A, and thereby, the communicationprotocol that may be used by protocol engine 250A to communicate withmass storage 28. In a similar fashion, the one or more commands,provided by processor core 218 to interface circuitry 204 as a result ofthe selection of the mode of operation of integrated circuit 40, alsomay result the selection of respective communication protocols that maybe used by each of the other protocol engines in interface circuitry 204to communicate with mass storage 28. Additionally or alternatively,these one or more commands also may select which protocol engines 250A,250B, . . . 250N may be enabled and/or operational, or disabled and/ornon-operational.

In addition, depending at least in part upon the selected mode ofoperation of integrated circuit 40, processor core 216 and/or RAIDoperation-related circuitry 240 may be either enabled to perform ordisabled from performing one or more operations involved in implementingand/or maintaining a RAID, such as, for example, RAID 29. For example,if processor core 216 and circuitry 240 are enabled to perform suchoperations, processor core 216 may execute, in response at least in partto, for example, one or more requests issued by host processor 12 tointegrated circuit 40 to store, retrieve, and/or rebuild user data inRAID 29, program instructions stored in memory 220 that may result inprocessor core 216 determining in accordance, for example, withconventional RAID techniques, locations in RAID 29 in which to storeand/or from which may be retrieved check data and/or user dataassociated with the check data. As used herein, “check data” means firstdata generated based at least in part upon second data and from whichthe second data may be regenerated at least in part. If the RAID levelimplemented in RAID 29 is equal to zero, check data may be absent fromRAID 29, and these locations may be comprise, for example, locations inRAID 29 of one or more stripes (not shown) of user data. If the RAIDlevel implemented in RAID 29 is greater than one, the check data maycomprise parity data and these locations may comprise, for example,locations in RAID 29 of one or more stripes (not shown) of such checkdata and/or user data. Alternatively, if the RAID level implemented inRAID 29 is equal to one (i.e., RAID 29 implements data mirroring), thecheck data may comprise a copy of the user data and these locations maycomprise, for example, locations of the user data and the redundant copyof the user data in respective mirrored volumes (not shown) in RAID 29.In this embodiment, processor core 216 and/or RAID calculation circuitry236 may utilize conventional RAID techniques to generate the check databased at least in part upon the user data and/or to regenerate the userdata based at least in part upon the check data. Depending upon theselected operating mode of integrated circuit 40, processor core 218 maysignal interface circuitry 204. This may result in one of the protocolengines (e.g., protocol engine 250A) transmitting to and/or retrievingfrom mass storage 28, via its associated interface 252A and one of thelinks 44 to which that interface 252A may be coupled, the user dataand/or check data. The user data and/or check data may be stored inand/or retrieved from RAID at the locations determined by processor 216.

Memory 39, memory 220, memory 224, and/or memory 228 may compriseprogram instructions that, when executed by integrated circuit 40, mayresult in, among other things, card 20 performing operations inaccordance with one embodiment. FIG. 5 is a flowchart that illustratesthese and other operations 600 that may be carried out in system 100, inaccordance with one embodiment.

As illustrated by operation 602, operations 600 may commence with theselection of the selected mode of operation of integrated circuit 40. Inthis embodiment, the selected mode of operation of integrated circuit 40may be selected, based upon and/or as a result, at least in part, of oneor more signals provided to GPIO interface circuitry 248 from selectorcircuitry 42, one or more signals provided to host bus interfacecircuitry 210 by host processor 12, execution by processor circuitry 202of one or more program instructions stored in memory 39, and/ordetection and/or discovery by circuitry 204 of one or more respectivecommunication protocols being used in one or more links 44.

For example, in this embodiment, selector circuitry 42 may comprise oneor more jumpers and/or one or more dual in-line package (DIP) switches43 that may be set (e.g., by a not shown human operator) in a pluralityof different configurations to select the selected operating mode ofintegrated circuit 40. That is, the plurality of differentconfigurations of the jumper and/or switches 43 may correspond torespective different operating modes of integrated circuit 40. When theone or more jumpers and/or one or more DIP switches 43 are set in aparticular configuration, the selector circuitry 42 may generate one ormore control signals that may correspond to and/or indicate the mode ofoperation of integrated circuit 40 that corresponds to that particularconfiguration. After, for example, a reset of integrated circuit 40,these one or more control signals may be supplied to processor cores 216and 218 via circuitry 246, circuitry 244, bus 254, bridge circuitry 208,and bus 206.

In response, at least in part, to these one or more control signals,processor core 218 may generate and supply to interface circuitry 204and/or host bus interface circuitry 210 one or more commands that mayselect, in accordance with the mode of operation of integrated circuit40 that corresponds to and/or is indicated by the one or more controlsignals, which of bus interfaces 212 and 214 is to be enabled ordisabled, respectively, which protocol engines 250A, 250B, . . . 250Nare to be enabled or disabled, respectively, and/or the protocols thatare to be implemented by protocol engines 250A, 250B, . . . 250N.Processor core 218 also may generate and supply to DMA circuitry 234 oneor more commands that may either enable DMA circuitry 234 to control ordisable DMA circuitry 234 from controlling, depending upon the mode ofoperation of integrated circuit 40 that corresponds to and/or isindicated by the one or more control signals, the exchange among I/Ointerface 204 and the other circuitry in integrated circuit 40 of dataand/or commands received or intended to be transmitted by I/O interfacecircuitry 204 via one or more links 44.

Also in response, at least in part, to these one or more control signalsfrom selector circuitry 42, processor core 216 may determine, inaccordance with the mode of operation of integrated circuit 40 thatcorresponds to and/or is indicated by the one or more control signals,whether processor core 216 and/or RAID operation-related circuitry 240are intended to be operative and/or enabled, or non-operative and/ordisabled, given the operating mode of integrated circuit 40 selected bythe jumpers and/or switches 43.

If processor core 216 determines that processor core 216 and/or RAIDoperation-related circuitry 240 are intended to be operative and/orenabled, processor core 216 may signal circuitry 240. This may result inprocessor core 216 and/or circuitry 240 performing one or moreoperations involved in implementing and/or maintaining a RAID, such as,for example, RAID 29.

Conversely, if processor core 216 determines that processor core 216and/or RAID operation-related circuitry 240 are intended to benon-operative and/or disabled, processor core 216 may signal circuitry240. This may result in processor core 216 and/or circuitry 240 beingdisabled from performing one or more operations involved in implementingand/or maintaining a RAID, such as, for example, RAID 29.

Alternatively or additionally, the one or more control signals fromselector circuitry 42 also may be supplied to circuitry 210, circuitry234, and/or circuitry 240. This may result in enabling or disabling ofbus interface circuitry 212, bus interface circuitry 214, circuitry 240,and/or circuitry 234 in accordance with the mode of operation ofintegrated circuit 40 that corresponds to and/or is indicated by the oneor more control signals.

Alternatively or additionally, in this embodiment, the selected mode ofoperation of integrated circuit 40 may be selected in operation 602,based upon and/or as a result, at least in part, of one or more signalsprovided to host bus interface circuitry 210 by host processor 12. Forexample, host bus interface circuitry 210 may include one or more memorylocations (not shown) that may contain one or more values that mayindicate the selected mode of operation of integrated circuit 40. Theseone or more memory locations may comprise, for example, one or moreconfiguration registers. After a reset of system 100, these one or morevalues may indicate a default mode of operation of integrated circuit 40in which an appropriate, predetermined one of interface circuitry 212and interface circuitry 214 is enabled, depending upon whether, forexample, bus 22 is a PCI-X bus or a PCI Express™ bus. Host processor 12may initiate and/or execute one or more configuration cycles, inaccordance with the bus protocol with which bus 22 may comply or becompatible, during which host processor 12 may provide one or morecontrol signals to circuitry 210 that may result in a change, at leastin part, of these one or more values to select the mode of operation inwhich integrated circuit 40 is desired to operate. That is, these one ormore values, as changed, at least in part by host processor 12, mayindicate a mode of operation in which integrated circuit 40 is desiredto operate. Prior thereto or contemporaneously therewith, a humanoperator of system 100 may select the desired mode of operation ofintegrated circuit 40, and may issue one or more commands to hostprocessor 12 via user interface system 16 that may result in hostprocessor 12 changing these one or more values such that the one or morevalues, as changed, indicates this desired mode of operation.

Thereafter, processor cores 216 and 218 may examine these one or morevalues stored in the one or more memory locations in host bus interfacecircuitry 210, and may determine therefrom the selected mode ofoperation of integrated circuit 40. Processor core 218 may generate andsupply to interface circuitry 204 one or more commands that may select,in accordance with the mode of operation of integrated circuit 40 thatcorresponds to and/or is indicated by these one or more values, whichprotocol engines 250A, 250B, . . . 250N are to be enabled or disabled,respectively, and/or the protocols that are to be implemented byprotocol engines 250A, 250B, . . . 250N. Processor core 218 also maygenerate and supply to DMA circuitry 234 one or more commands that mayeither enable DMA circuitry 234 to control or disable DMA circuitry 234from controlling, depending upon the mode of operation of integratedcircuit 40 that corresponds to and/or is indicated by the one or morevalues, the exchange among I/O interface 204 and the other circuitry inintegrated circuit 40 of data and/or commands received or intended to betransmitted by I/O interface circuitry 204 via one or more links 44.

Processor core 216 may determine, in accordance with the mode ofoperation of integrated circuit 40 that corresponds to and/or isindicated by the one or more values, whether processor core 216 and/orRAID operation-related circuitry 240 are intended to be operative and/orenabled, or non-operative and/or disabled, given the operating mode ofintegrated circuit 40 indicated by the one or more values.

If processor core 216 determines that processor core 216 and/or RAIDoperation-related circuitry 240 are intended to be operative and/orenabled, processor core 216 may signal circuitry 240. This may result inprocessor core 216 and/or circuitry 240 performing one or moreoperations involved in implementing and/or maintaining a RAID, such as,for example, RAID 29.

Conversely, if processor core 216 determines that processor core 216and/or RAID operation-related circuitry 240 are intended to benon-operative and/or disabled, processor core 216 may signal circuitry240. This may result in processor core 216 and/or circuitry 240 beingdisabled from performing one or more operations involved in implementingand/or maintaining a RAID, such as, for example, RAID 29.

Alternatively or additionally, circuitry 234 and/or circuitry 240 mayexamine the one or more values stored in circuitry 210. This may resultin enabling or disabling of circuitry 240 and/or circuitry 234 inaccordance with the mode of operation of integrated circuit 40 thatcorresponds to and/or is indicated by the one or more values.

Alternatively or additionally, in this embodiment, the selected mode ofoperation of integrated circuit 40 may be selected in operation 602,based upon and/or as a result, at least in part, of execution byprocessor circuitry 202 of one or more program instructions stored inmemory 39. That is, according to this embodiment, different respectiveoperating modes of integrated circuit 40 may be associated withdifferent respective firmware program instruction set images that whenexecuted, at least in part, by processor core 216 and processor core 218may result in the respective operating modes being associated with theserespective images being selected, and also may result in integratedcircuit 40 operating in the respective operating modes. In thisembodiment, only a single such firmware program instruction set imagemay be stored in memory 39, memory 220, and/or memory 224. This singlefirmware program instruction set image may comprise one or more firmwareprogram instructions that may be executed by processor cores 216 andprocessor 218 after, for example, a reset of integrated circuit 40. Thismay result in processor core 218 generating and supplying to interfacecircuitry 204 one or more commands that may select, in accordance withthe mode of operation of integrated circuit 40 that is associated withthe single firmware program set image stored in memory 39, memory 220,and/or memory 224, which of interfaces 212 and 214 is to be enabled, andwhich protocol engines 250A, 250B, . . . 250N are to be enabled ordisabled, respectively, and/or the protocols that are to be implementedby protocol engines 250A, 250B, . . . 250N. This may also result inprocessor core 218 generating and supplying to DMA circuitry 234 one ormore commands that may either enable DMA circuitry 234 to control ordisable DMA circuitry 234 from controlling, in accordance with the modeof operation of integrated circuit 40 that is associated with the singlefirmware program set image stored in memory 39, the exchange among I/Ointerface 204 and the other circuitry in integrated circuit 40 of dataand/or commands received or intended to be transmitted by I/O interfacecircuitry 204 via one or more links 44.

The execution of these one or more program instructions by processorcore 216 also may result in processor core 216 determining, inaccordance with the mode of operation of integrated circuit 40 that isassociated with this single firmware program instruction set image,whether processor core 216 and/or RAID operation-related circuitry 240are intended to be operative and/or enabled, or non-operative and/ordisabled, given this operating mode of integrated circuit 40.

If processor core 216 determines that processor core 216 and/or RAIDoperation-related circuitry 240 are intended to be operative and/orenabled, processor core 216 may signal circuitry 240. This may result inprocessor core 216 and/or circuitry 240 performing one or moreoperations involved in implementing and/or maintaining a RAID, such as,for example, RAID 29.

Conversely, if processor core 216 determines that processor core 216and/or RAID operation-related circuitry 240 are intended to benon-operative and/or disabled, processor core 216 may signal circuitry240. This may result in processor core 216 and/or circuitry 240 beingdisabled from performing one or more operations involved in implementingand/or maintaining a RAID, such as, for example, RAID 29.

Alternatively or additionally, in this embodiment, the selected mode ofoperation of integrated circuit 40 may be selected in operation 602,based upon and/or as a result, at least in part, of detection and/ordiscovery by circuitry 204 of the one or more respective communicationprotocols being used by one or more links 44. That is, circuitry 204 mayexamine signals transmitted to circuitry 204 via one or more links 44that may embody data and/or commands, and may detect and/or discover,based at least in part upon such examination, one or more respectivecommunication protocols via which such commands and/or data may havebeen transmitted to circuitry 204 via one or more links 44. Circuitry204 may provide one or more signals to processor core 218 that mayindicate these one or more detected and/or discovered protocols, and mayselect, in accordance with these detected and/or discovered protocols,which protocol engines 250A, 250B, . . . 250N are to be enabled ordisabled, respectively, and/or the one or more protocols that are to beimplemented by protocol engines 250A, 250B, . . . 250N. Based at leastin part upon the indication provided to processor core 218 by circuitry204, processor core 218 may generate and supply to DMA circuitry 234 oneor more commands that may enable DMA circuitry 234 to control theexchange among I/O interface 204 and the other circuitry in integratedcircuit 40 of data and/or commands received or intended to betransmitted by I/O interface circuitry 204 via one or more links 44. Oneor more signals provided to GPIO interface circuitry 248 from selectorcircuitry 42, one or more signals provided to host bus interfacecircuitry 210 by host processor 12, and/or execution by processorcircuitry 202 of one or more program instructions stored in memory 39may be used to select, for example, in the manner described previously,whether processor core 216 and/or RAID operation-related circuitry 240are intended to be operative and/or enabled, or non-operative and/ordisabled, and which of interfaces 212 and 214 is to be enabled.

After the selected mode of operation of integrated circuit 40 has beenselected as a result of operation 602, integrated circuit 40 may operatein the selected mode of operation, as illustrated by operation 604 inFIG. 5. For example, one operating mode that may be selected as a resultof operation 602 may be carried out by integrated circuit 40 in system100′ shown in FIG. 4. Unless stated to contrary, the construction andoperation of system 100′ may be substantially identical to theconstruction and operation of system 100 shown in FIG. 1. In this onemode of operation of integrated circuit 40, interface circuitry 204 mayexchange data and/or commands with RAID 29, based at least in part, uponcommands received from processor core 218. Processor core 216 andcircuitry 240 may be disabled, and one or more operations comprised incarrying out and/or facilitating operations involved in implementingand/or maintaining RAID 29 may be executed by a RAID controller card504, instead of by processor core 216 and/or circuitry 240. In system100′, card 504 may comprise a bus interface 510. Depending upon, forexample, whether bus 22 comprises a PCI Express™ bus or a PCI-X bus,system 100′ may comprise a circuit card slot 502 that may include acircuit card slot 510 that may comprise, for example, a PCI Express™ orPCI-X bus compatible or compliant expansion slot or interface 506.Interface 506 may comprise a bus connector 508 may be electrically andmechanically mated with a mating bus connector 512 that may be comprisedin a bus expansion interface 510 in circuit card 504. When connector 508is mated with connector 512, card 504 may exchange data and/or commandswith other devices, such as, for example, card 20 via bus 22.

In system 100′, data and/or commands received by card 20 from RAID 29that are intended to undergo and/or to be used in one or more one ormore operations comprised in carrying out and/or facilitating operationsinvolved in implementing and/or maintaining RAID 29 may be transmittedfrom integrated circuit 40 via bus 22 to card 504. Card 504 may carryout such operations and transmit to integrated circuit 40 other commandsand/or data that may represent and/or embody the results of suchoperations. Processor core 218 may provide one or more control signalsto interface 204 that may result in interface 204 transmitting theseother data and/or commands to RAID 29 to implement and/or maintain, atleast in part, RAID 29.

Alternatively, in another mode of operation of integrated circuit 40,instead of and/or in addition to exchanging data and/or commands withintegrated circuit 40 via bus 22, card 504 may exchange data and/orcommands with integrated circuit 40 via one or more communication links500 that may be coupled to one or more respective physical interfaces252A, 252B, . . . 252N. That is, in this other mode of operation ofintegrated circuit 40, a subset of physical interfaces 252A, 252B, . . .252N may be coupled to one or more links 44, and a different subset ofphysical interfaces 252A, 252B, . . . 252N may be coupled to card 504via one or more links 500. In this other mode of operation of integratedcircuit 40, processor core 216 and circuitry 240 may be disabled, anddata and/or commands received by card 20 from RAID 29 that are intendedto undergo and/or to be used in one or more operations comprised incarrying out and/or facilitating operations involved in implementingand/or maintaining RAID 29 may be transmitted from integrated circuit 40via one or more links 500 to card 504. Card 504 may carry out suchoperations and transmit to integrated circuit 40 other commands and/ordata that may represent and/or embody the results of such operations.Processor core 218 may provide one or more control signals to interface204 that may result in interface 204 transmitting these other dataand/or commands to RAID 29 to implement and/or maintain, at least inpart, RAID 29.

Thus, in summary, one system embodiment may comprise a circuit cardcapable of being coupled to storage. The circuit card may include anintegrated circuit. The integrated circuit may be capable of operatingin a selected mode of operation. The integrated circuit may comprisefirst circuitry and second circuitry. The first circuitry may be capableof performing at least one operation that comprises, at least in part,generating check data based at least in part upon other data,regenerating the other data based at least in part upon the check data,and/or determining locations of the check data and the other data in thestorage. The second circuitry may be capable of controlling, at least inpart, at least one interface to transmit from and/or receive at theintegrated circuit the check data and/or the other data. Depending atleast in part upon the selected mode of operation of the integratedcircuit, the first circuitry may be enabled to perform or disabled fromperforming the at least one operation.

Also in summary, one system embodiment may comprise a circuit card thatincludes an integrated circuit. The circuit card may be capable of beingcoupled to a bus. The integrated circuit may be capable of operating ina selected mode of operation. The integrated circuit may compriseprocessor circuitry and interface circuitry. The processor circuitry mayinclude a plurality of processor cores. The interface circuitry may becapable of communicating in accordance a plurality of differentprotocols. At least one of the processor cores may be capable of issuinga command to the interface circuitry to communicate in accordance withat least one of the plurality of different protocols that corresponds tothe selected mode of operation of the integrated circuit.

Advantageously, the integrated circuits of these system embodiments mayoffer enhanced communication capabilities, and may communicate using agreater number of host bus and communication protocols, compared to theprior art. Also advantageously, the host bus and/or communicationprotocols used by these integrated circuits of these system embodimentsmay be selected. Additionally, the integrated circuits of these systemembodiments may include single respective packages and/or “foot prints”that may include circuitry that may be used to perform RAID-relatedoperations and/or communication protocol operations. Advantageously,this may improve the utility and/or versatility of the integratedcircuits of these system embodiments, since these integrated circuitsmay be used to perform such RAID-related operations or may be usedtogether with other RAID controller devices that may perform suchoperations.

The terms and expressions which have been employed herein are used asterms of description and not of limitation, and there is no intention,in the use of such terms and expressions, of excluding any equivalentsof the features shown and described (or portions thereof), and it isrecognized that various modifications are possible within the scope ofthe claims. Accordingly, the claims are intended to cover all suchequivalents.

1. A method comprising: operating an integrated circuit in a selectedmode of operation, the integrated circuit comprising processor circuitryand interface circuitry, the processor circuitry including a pluralityof processor cores, the interface circuitry being capable ofcommunicating in accordance a plurality of different protocols, at leastone of the processor cores being capable of issuing a command to theinterface circuitry to communicate in accordance with at least one ofthe plurality of different protocols that corresponds to the selectedmode of operation of the integrated circuit.
 2. The method of claim 1,wherein: the at least one of the plurality of different protocolscomprises at least two of the plurality of different protocols.
 3. Themethod of claim 1, wherein: the interface circuitry comprises aplurality of protocol engines and respective physical layer interfacecircuitry; and the protocol engines are capable of communicating via therespective physical layer circuitry in accordance with the plurality ofdifferent protocols.
 4. The method of claim 3, wherein: the commandindicates respective protocols, selected from the plurality of differentprotocols, via which the protocol engines are requested to communicate.5. The method of claim 1, wherein: the interface circuitry comprises businterface circuitry; and the plurality of different protocols comprisesa plurality of different bus protocols.
 6. The method of claim 1,further comprising: selecting the selected mode of operation, theselecting of the selected mode of operation comprising supplying to theintegrated circuit one or more signals that indicate, at least in part,the selected mode of operation.
 7. The method of claim 1, furthercomprising: selecting the selected mode of operation, the selecting ofthe selected mode of operation comprising executing one or more programinstructions by the integrated circuit, execution of the one or moreprograms resulting, at least in part, in selection of the selected modeof operation.
 8. An apparatus comprising: an integrated circuit capableof operating in a selected mode of operation, the integrated circuitcomprising processor circuitry and interface circuitry, the processorcircuitry including a plurality of processor cores, the interfacecircuitry being capable of communicating in accordance a plurality ofdifferent protocols, at least one of the processor cores being capableof issuing a command to the interface circuitry to communicate inaccordance with at least one of the plurality of different protocolsthat corresponds to the selected mode of operation of the integratedcircuit.
 9. The apparatus of claim 8, wherein: the at least one of theplurality of different protocols comprises at least two of the pluralityof different protocols.
 10. The apparatus of claim 8, wherein: theinterface circuitry comprises a plurality of protocol engines andrespective physical layer interface circuitry; and the protocol enginesare capable of communicating via the respective physical layer circuitryin accordance with the plurality of different protocols.
 11. Theapparatus of claim 10, wherein: the command indicates respectiveprotocols, selected from the plurality of different protocols, via whichthe protocol engines are requested to communicate.
 12. The apparatus ofclaim 8, wherein: the interface circuitry comprises bus interfacecircuitry; and the plurality of different protocols comprises aplurality of different bus protocols.
 13. The apparatus of claim 8,wherein: the integrated circuit is capable of receiving one or moresignals that indicate, at least in part, the selected mode of operation.14. The apparatus of claim 8, wherein: the processor circuitry iscapable of executing one or more program instructions, execution of theone or more programs resulting,. at least in part, in selection of theselected mode of operation.
 15. An article comprising: a storage mediumhaving stored thereon instructions that when executed by a machineresult in the following: operating an integrated circuit in a selectedmode of operation, the integrated circuit comprising processor circuitryand interface circuitry, the processor circuitry including a pluralityof processor cores, the interface circuitry being capable ofcommunicating in accordance a plurality of different protocols, at leastone of the processor cores being capable of issuing a command to theinterface circuitry to communicate in accordance with at least one ofthe plurality of different protocols that corresponds to the selectedmode of operation of the integrated circuit.
 16. The article of claim15, wherein: the at least one of the plurality of different protocolscomprises at least two of the plurality of different protocols.
 17. Thearticle of claim 15, wherein: the interface circuitry comprises aplurality of protocol engines and respective physical layer interfacecircuitry; and the protocol engines are capable of communicating via therespective physical layer circuitry in accordance with the plurality ofdifferent protocols.
 18. The article of claim 17, wherein: the commandindicates respective protocols, selected from the plurality of differentprotocols, via which the protocol engines are requested to communicate.19. The article of claim 15, wherein: the interface circuitry comprisesbus interface circuitry; and the plurality of different protocolscomprises a plurality of different bus protocols.
 20. The article ofclaim 15, wherein: the operating in the selected mode of operation is inresponse, at least in part, supply to the integrated circuit of one ormore signals that indicate, at least in part, the selected mode ofoperation.
 21. The article of claim 15, wherein: the instructionscomprises at least one set of program instructions whose execution bythe machine results, at least in part, in the operating in the selectedmode of operation.
 22. A system comprising: a circuit card including anintegrated circuit, the circuit card being capable of being coupled to abus, the integrated circuit being capable of operating in a selectedmode of operation, the integrated circuit comprising processor circuitryand interface circuitry, the processor circuitry including a pluralityof processor cores, the interface circuitry being capable ofcommunicating in accordance a plurality of different protocols, at leastone of the processor cores being capable of issuing a command to theinterface circuitry to communicate in accordance with at least one ofthe plurality of different protocols that corresponds to the selectedmode of operation of the integrated circuit.
 23. The system of claim 22,further comprising: a circuit board comprising the bus and a businterface slot, the circuit card being capable of being coupled to thebus interface slot.
 24. The system of claim 23, wherein: the circuitboard also comprises a processor that is capable of supplying one ormore control signals to the circuit card via the bus and bus interfaceslot, the supplying of the one or more control signals to the circuitcard resulting, at least in part, in selection of the selected mode ofoperation.
 25. The system of claim 22, wherein: the interface circuitryis capable of being coupled to storage.
 26. The system of claim 25,wherein: the storage comprises a redundant array of independent disks(RAID).
 27. The system of claim 22, wherein: the interface circuitrycomprises first bus interface circuitry capable of communicating inaccordance with a first bus protocol, and a second bus interface that iscapable of communicating in accordance with a second bus protocol. 28.The system of claim 22, wherein: the interface circuitry includes businterface circuitry and network interface circuitry.
 29. The system ofclaim 22, wherein: the circuit card further comprises first memory; andthe integrated circuit further comprises a second memory and memorycontroller circuitry to control, at least in part, the first memory andthe second memory.